Roll for rolling molten glass



Feb. 14, 1928.

H. R. SCHUTZ ROLL FOR ROLLING MOLTEN GLASS Filed Maroh 3 1927 Patented Feb. 14, 1928.

UNITED STATES PATENT OFFICE.

HAROLD R. SCHUTZ, OF TOLEDO, OEIO, ASSIGNOR T0 TEE EDWARD FORD ILATE GLASS 00., OF ROSSFORD, OHIO, A OOBPORATION O1! OHIO.

ROLL FOR'ROLLING- MOLTEN GLASS.

Applioaiiion filed March 3, 1927. Serial N0. 172,266.

This invention relates to the manufacture of plate or sheet glass, by 'the intermittent, as distinguished from the continuous, rolling method.

In the use of this method, a quantity of -molten glass is customarily deposited in a receptacle in contact at one side with a pair of rolls by which the glass is rolled out in sheet or plate form, the size of the sheet depending 011 the quantity of glass in the receptacle, all of which isusually rolled out in a single operation. The sheot is then annealed, ground and polished.

The rolls employed are usually of hollow form with arelatively thick solid wall of uniform thickness. These rolls are ordina- 1'ily coole d by a circulating air, water 01 other cooling fluid therethrough, and due to their circular interior forma, present a minirnum of surface to the cooling medium. The Wall must be made of considerable thickness to provide a suflicient 'mechanical strength, so that a roll of the length ordinarily used will have th e necessary res1stance to lateral deflection occasioned by the rolling pressure.

It is found in practice that when rolls of this character are ab rest the prolonged contact 01: themolten glass with the portion of the rolls exposed to the receptacle causes a high heating and more rapid expansion of s'ueh portions than others of the rolls resulting in a hump or bulge at such po1nts. When the rolls in this condition are rotated about their axes in the process of reducing the molten g1ass to sheet form, alternate thin and thick sections are produced in the sheet by the irregular -forms of the roll peripheries. The irregular sheet surface must be redu'ced by grinding thereby requ1nng considerably more work and time in t he grinding operation t han would othermse be necessary .and add1ng accord1ngly to the expense of production. It isapparent that the irregular heating 013 the rolls and the consequent irregular formation of the sheets is also present, but to a less extexit, when the rolls are continuously rotated.

In order to reduce to a minimum these irregularities in thethickness of the formed sheet, it has been customary t0 rotate the rolls faster than Would otherwise ordinarily dllcing rolled sheet 01 plate glass. Fig. 2 is be the case. Thispractice however, pro- V duces a sheet hav1ng a rounded end of greater length than desired, which it is necessa'ry to cutaway to produce a straight end. This results in a considcrable loss of glass which could otherwise be used to produce a sheet of greater size.

The object of this invention is to provide a roll which Will reduce the above object1ons to a minimum, and this is accomplished by providing a hollow roll having a relatively thin Wall o1 shell to efi'eet a rapid d1ssipation of heat therethrough to the intel'l0l' cooling means and also to provide the 1ntenor of' said Wall with a plurality of l'ibS or fins both to increasethe heat radiat- .ing efliciency of the inner surface of the roll und to strengthen 01 reinforce the thin Wall ugzunst compressing or deflecting forces.

The invention is fully described in the following speoification' and one embodirnent thereof illustratecl in -tl1e accomjaanying drawings, in which- Figuro 1 is a oentral longitudinal sect1onal v1ew, more orless in diagram, of an appartus embodying the invention for proan enlarged central longitudinal section of one 0f the rolls embodying the invention,

"und Fig. 3 is an enlarged cross-section on the line 33 in Fig. 2.

Referring to the drawings, 1 designates a roceptacle for molten glass 2 such receptacle having an open side, Which is closed 01' partially closed by a pair of rolls 3, 3 between which the glass from the receptacle is rolled and advanced therefrom in the form of a sheet or plate 4. The sheet formed by the rolls is shown as passing, in the present instance, dwn an inclined slide 5 and onto a subjaoent transporting table 6, as well 1111- derstood in the art.

It will be noted that in the use 0f an apparaCus of this character fragmentary portions of the surfaces of the tworolls are exposed to the molten g1ass in the receptacle, so that such portions, both during a rotation of t-he rolls am]. When stationary, are more highly heated than the other portions of the rolls, thereby eifecting an expansion of the metal ab such point and the consequent forming of a bulge 01 hmp 0n the roll periphery. This irregular form of the roll surface imparts sucoessive thick and (hin sections to the rolled sheet, thereby necessitating greater work in the grinding operation to reduce the sheet surfaces to a true plane than would be necessary if rolls of true cylindrical form were used.

The 1011s3, 3 are of hollow form t0 facilitate the passage of a cooling fiuid, such, for instance as air or water therethrough, as well understood in the art, the fluid being introduced into the roll und discharged therefrom through axia1 passages in the end trunnions 7 of the rolls. These trannions, in the present instance, are provided 011 end plates 8 secured t0 the roll in closing relation t0 the end openings thereof. In order t0 facilitate the rapid conduction Of heat through the roll Wall to the cooling fluid the Wall is preferably made quite thin, and in order t0 provide strength f0r such Wall against inward deflection under rolling stresses and also to present a larger radiating surface to the cooling fluid, the inner surface of the roll Wall is provided With 21 plurality of Webs 01 ribs 9, preferably running throughout the length 0f the roll and spaced transversely thereof.

By the use of a roll of this construction, so far as I am aware a more rapid transmission of heat from the hottest part of the roll t0 the c001 i11g fluid will take place than with the forms of rolls heretofore used, and this Will result in less distortion in the roll and tend t0 maintain the shape of the same nearer that of a true cylinder than heretofore. It is possible with this form of roll to rotate it at a slower speed at the starb of the rolling operation than is practical with the rolls heretofore used and thereby produce a comparatively flatsheet with a blunter end than heretofore. 011 account of its more eflicient cooling feature and the fact that it has a minimum of distortion under varying heat conditions made possible by the use of the chinnerwalls, combined with the internal ribb'ing of the Same, it is possible with the use of this roll to produce more glass of a uniform thicknass than can be produced, so far as I am aware, with the types of rolls heretofore employed.

II21Villg thus described my invention, what I clai1n as new and desire to secure by Letters Patent is 1. A. roll for contact with und shaping molten g1ass, said roll being of hollow cylindrical form for the circulation 0f a cool ing fluid therethroughand having the inner surface of its circumferentialwall ribbed to increasg the heat radiating surface thereof.

2. A metal roll for contact with and shaping molten glass, said roll being hollow to permit the circulation of 2L cooling fluid therethrough andhaving a relatively thin circumferential Wall with the inne1 surface thereof ribbed to strengthen the Wall against distortion under rolling stresses and t0 facilitafe heat radiation to the cooling fluid.

3. A metal roll for contact with and shaping molten glass, said roll being hollow to permit the cireulation of a cooling fiuid. therethrough and having a relatively thin circumferential Wall with the inner surface thereof longitudinally ribbed t0 reinforce the Wall against distortion under rolling stresses and to facilitate heat radiation to the cooling fiuid.

In a sheet glass rolling apparatus, a receptacle for containing a batch of molten glass, a p.air of rolls exposed to the molten glass at one side of the receptacle and assisting in confining the molten glass within the receptacle, said ro11s being spaced to adaptthem to be turned t0 eifect a rolling 0f the glass in sheet form from the receptac1e and being h0110w to permit the circulation of a cooling fiuid therethrough and one at least having a relatively thin circumferential wa1l permitting a rapid dissipation 0f heat inwardly therethrough fo the cooling fluid and having its inner peripheral surface ribbed to strengthen the Wall against distortion under ro1ling stresses and to incr lease the heat rad iating eificiency of the r0 1.

In testim'ony whereof I have hereunto Signed my name to this specification.

HARQLD R. SCHU. 

